Did my best friend come out to me?

Hey so I am from a fairly small, conservative town in Massachusetts. I went to college with a friend, and while we all always suspected he was gay he never said anything. Our college group of friends are very liberal but everyone at home is super conservative so I thought maybe he was worried it would get out. Anyway, he never expressed any interest in men or women etc. Literally whole of college and nothing and we graduated 4 years ago and still nothing. Last week we meet up for a drink and we're just talking about what we've been up to and he goes 'yeah I met this guy for a drink off tinder' and I'm actually like 'holy cow what' (in my head) but we just have a totally normal conversation about how his drink went and what happened and that he enjoyed it but the guy hasn't been in touch. I asked a few of our other close friends and he's said nothing to them, so I'm pretty sure I'm the only one he told.Two questionsDid he come out?What should I say? I'm worried because I 'under reacted' (ie. I played along with his tone of it being very casual) that he feels like either I didn't understand or I'm not okay with it which is not the case - I've been worried about him and his happiness and always wanted him to be himself but didn't want to push him into saying anything if he wasn't ready. He hasn't mentioned anything since and I'm terrified I messed it up.